The ability to provide the consumer with a greater number of electronic services has become increasingly important for commercial success in the telecommunications industry. As has recently become the case, the long distance telecommunication exchange companies, the local area exchange companies, and local cable access television (CATV) companies have all sought out the technology to provide multiple media services to the local subscribers, such as an individual or a business. The services sought to be provided by any one of the above concerns includes enhanced pay-per-view, video-on-demand, interactive television, interactive games, image networking, video conversing, video telephony, CATV, and telephone switched services (including ISDN). In order to provide any combination of the above services in an economically viable manner, a distribution network of substantial capacity is required. Capacity, in this sense, refers primarily to the information carrying capability, which is substantially related to the broadcast frequency spectrum bandwidth of the transmission medium. Further, the network must be capable of being upgraded for the next evolution in broadband access architecture.
A transmission medium with the necessary capacity to make the multitude of services desired by consumers is optical fiber. However, it is not economically feasible to deploy an all fiber optic network from central offices to individual residences at one time. Rather, the current telecommunications network is undergoing an evolution in which coaxial cable and two wire pairs are being gradually replaced by fiber optic cable.
During this evolution, a so called hybrid fiber-coax network has been created that employs newly installed fiber cable and existing coaxial cable networks to provide the wide-band services to consumers. Such a network is the subject of a co-pending patent application Ser. No. 08/554,332 of Beecher, et. al., filed Mar. 31, 1998 and entitled "Upgradeable Fiber-Coax Network", now U.S. Pat. No. 5,699,176 the text of which is herein incorporated in its entirety.
Briefly stated, one type of hybrid fiber-coax network employs passive optic components at each fiber-coax distribution node that enables optical fiber to be deployed beyond the fiber-coax distribution nodes alongside the coax distribution network up to up to optical network units substantially located with each existing line extention amplifier (LEA). This configuration may be referred to as fiber-to-the-amplifier (FTTA). Preferably, optic network units (ONU's) are substantially located with the LEA's of the coax distribution network and provide switched telecommunications services by bypassing the LEA's. The coaxial network continues to provide broadcast cable TV.
A second type of hybrid fiber/coax network features passive optic components deployed beyond the fiber-coax distribution nodes alongside the coax distribution network up to optical network units substantially located at each existing line extension amplifier (LEA) as before. From the optical network units, coaxial cable is installed to each living unit. In this configuration, both broadband, narrowband, and switched services may be provided to the subscribers in direct competition with existing services provided via a coaxial network.
However, these hybrid fiber-coax cable networks are still unable to meet the capacity and reliability demands that currently exist and continue to grow into the future. An all fiber network can meet these demands, however, mass deployment is not economically and logistically possible. The existing telecommunications network is vast and will require significant man hours to accomplish a total conversion. Also, business and private consumers have grown accustomed to reliable telecommunications service such that significant disruptions are intolerable. In the case of businesses, an interruption of telecommunications services can cause significant financial loss. Consequently, there is a need for a method to upgrade existing fiber/coax networks into all fiber networks with a minimum of disruption of service to consumers.